1. Field of the Invention
The invention relates to a dilatation catheter having an evertable balloon element which is attached to the distal end of the catheter and stored in inverted condition in the catheter. The improved catheter of the invention comprises an elongated annular balloon having a distal dilating portion and a proximal, pleated connector portion which interconnects the dilating portion with the interior of the catheter and which enables the provision of a passageway through the catheter which always remains open.
2. Description of the Prior Art
The closest prior art of which we are aware is the third embodiment (FIGS. 7-10) of our prior patent, Fogarty et al. No. 4,271,839.